Since 2010 the demand of carbon fibers has been increased by a factor of 3, reaching approximately 98 k tons in 2020. Carbon fibers stand out in terms of light weight, high strength, electrical conductivity and chemical inertness. To implement carbon fibers in applications such as for making composite structures for electric vehicles and supercapacitors for energy storage devices, it is indispensable to develop new inexpensive precursors to replace more expensive PAN-based or mesophase pitch-based precursors. This investigation shows how asphaltenes, which are obtained as a by-product from bitumen partial upgrading, can play an important role as such. Bitumen production from oil sands is essential for energy production. It is expected to reach approximately 3.5 M barrels per day in 2030 in Alberta alone. Part of produced bitumen will be partial upgraded prior to pipeline transportation, which leads to a vast amount of asphaltenes. This investigation demonstrates the fabrication of green fibers using asphaltenes as carbon precursors via melt spinning and focuses on the oxidation step to enable a successful conversion of such fibers into carbon fibers. The main challenge is to circumvent remelting of the fibers during the fabrication process since the used asphaltenes exhibit a softening point below 200 °C. This is realized by using an acid pretreatment before any further heat treatments. The fibers are further used as electrode materials for energy storage. Fibers are decorated with V2O5 using a facile dipping procedure followed by heat treatment &lt;500 °C (Scheme 1). Different heat treatments at different temperatures are carried out. The V2O5@CF electrodes are tested in 1 M Li2SO4 electrolyte using a symmetrical coin cell set-up. The device shows a combination of battery-like Li+-intercalation and electric double layer type energy storage with a performance of 115 F g-1 (at 0.5 Ag-1) or 8 mAh g-1 as a battery-like system. Owing to high density of the material, the volume specific performance is calculated to be 54 F cm-3 or 4 mAh cm-3.

Fabrication of V2O5 decorated carbon fibers using asphaltene from solvent-de-asphalting for energy storage application

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.